#include <iostream>
#include <stdio.h>

using namespace std;

int main() {
  int n, T;
  while (cin >> n >> T) {
    int left = 1, right = n;
    int ans = 0;
    while (left != right) {
      int mid = (left + right) / 2;
      int a = mid - left;
      int b = right - mid;
      if (a >= b) {
        right = mid - 1;
      } else {
        left = mid + 1;
      }
      ans++;
    }
    if (ans <= T)
      cout << ans << endl;
    else
      cout << "Impossible" << endl;
  }
  return 0;
}